Method of making bicycle crank-hangers.



H. G. CARLSON.

METHOD OF MAKING BICYCLE CRANK HANGERS. APPLI-CATION FILED JULY 26, 1912.

1,165,316. Patented Dec. 21, 1915.

2 SHEETS-SHEET I.

[n venzor if Zorn-5y H; e. CARLSON.

MEWIHOD OF MAKING BICYCLE CRANK HANGERS.

APPLICATION FILED JULY 26. 1912.

1 165,31 6. Patented D65. 21, 1915.

2 SHEETS-SHEET 2. 1 3 6 COLUMBIA PLANOURAPH COIIWASHINGTON, D. c.

HJA LMAR G. CARLSON,

0F WORCESTER, MASSACHUSETTS, ASSIGNOR T0 ROCKWOOD SPRINKLER COMPANY OF MASSACHUSETTS, 0F WORCESTER, MASSACHUSETTS, A

CORPORATION OF MASSACHUSETTS.

METHOD OF MAKING BICYCLE CRANK-HANGERS.

' Specification of Letters Patent.

Patented Dec. 21, 1915.

Application filed July 26, 1912. Serial No. 711,663.

To all whom it may concern:

Be it known that I, HJALMAR G. OARLsoN, a citizen of the United States, residing at Worcester, in the county of Worcester and Commonwealth of Massachusetts, have invented a new and useful Improvement in Methods of Making Bicycle Crank-Hangers, of which the following is a specification.

My invention relates to crank hangers arranged to contain the crank and crank bearing of a bicycle and which are supported by the frame of the bicycle, and it consists of an improved method of constructing the hanger from a single piece of metal with fastening lugs integral with the same.

The objects of my invention are to reduce the cost of manufacture and to secure accuracy of shape, which I attain by the method hereinafter described and illustrated in the accompanying drawings, in which 7 Figure 1 is a plan view of the blank from which the hanger is constructed. Fig. 2 is an edge view of the same. Fig. 3 is a side view of the punch by which the first step in the construction of my hanger is accomplished. Fig. 4 is an edge view of the blank after being subjected to the action of the punch shown in Fig. 3. Fig. 5 is a side view of the die employed in connection with the punch shown in Fig. 3. Fig. 6 is a side view of the punch used in the second step of my method. Fig. 7 is an edge view of the blank after being subjected to the action of the punch shown in Fig. 6. Fig. 8 is a plan view of the same. Fig. 9 is an edge view of the blank after the flanges 15 have been formed thereon, and Fig. 10 is a perspective view of the completed hanger.

Similar reference characters refer to similar parts in the difierent figures.

Starting with a blank 1 of the shape shown in Figs. 1 and 2 and having holes 2, 2 and 3, 3 punched in the same, I subject the blank 1 to the action of a punch 4 and a die 5, shown in Figs. 3 and 5, by which it is formed in the shape of the blank 6 shown in Fig. 4, with its opposite ends turned upwardly at 7, 7 and having a pair of recessed lugs 8 formed in its ends by the curved sections 9 of the punch 4. Leaving the blank 6 in the die 5 I apply to it the punch 10, shown in Fig. 6, which is the same as the punch 4 shown in Fig. 3, except that shoulders 11 extend around the curved portions 9 of the punch 10, by means ofgvhich the upper irregular edges 12 of the lugs 8 formed on the blank 6 by the first punch 4 are upset and straightened, as shown at 13, 13 in Fig. 7, which represents the blank in edge View, and in Fig. 8 which shows the blank in top view.

After the blank is shaped as shown in Figs. 7 and 8, flanges 15 are formed around the openings 2, 2 and 3, 3, Fig. 9, by suitable punches and dies. The blank is then bent into a circular form with the lugs 8 abutting, as shown in Fig. 10. Holes 16 are bored directly through each pair of lugs 8 to secure a bolt inserted therein to draw the edges 13 of the lugs 8 toward each other. Short pieces of pipe 17 are inserted in the openings 2, 2 and 3, 3 to which the frame of the bicycle is attached in a manner employed at the present time.

The hanger when constructed in accord ance with my improved method is shown in perspective view in Fig. 10, and does not differ essentially from the hangers noW in common use. By the method of manufacture as at present practised, however, the hanger is formed from a piece of circular pipe, the lugs are formed therein or are attached thereto, and the pipe is then cut apart to enable the crank bearing to be pinched therein.

By my improved method I form the hanger from a flat blank and shape the lugs before the blank is pressed into circular form. The cost of construction is thereby greatly diminished, and the accurate shape of the lugs and true circular shape of the hanger secured.

I claim,

The herein described method of making a bicycle crank hanger, comprising the stamping of recessed lugs on the ends of a fiat blank or plate, the upsetting of the top edges of said lugs, and the bending of said blank into circular form to bring the edges of lugs at opposite ends of the blank into engagement, as and for the purpose specified.

Dated this 22nd day of July 1912.

HJALMAR G. CARLSON. Witnesses PENELOPE CoMnnnBAoH, RUrUs B. FOWLER.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. 0. 

